Investing.com -- Eli Lilly said Wednesday that its weight-loss medication Zepbound (tirzepatide) demonstrated superior efficacy over Novo Nordisk (NYSE:NVO)'s Wegovy (semaglutide) in the phase 3b SURMOUNT-5 trial, showing an average weight loss of 20.2% compared to Wegovy's 13.7%.
The company explained that the trial included adults with obesity or overweight who had at least one weight-related medical condition but did not have diabetes.
Zepbound is said to have outperformed Wegovy on both the primary endpoint and all five key secondary endpoints at 72 weeks.
Notably, 31.6% of participants on Zepbound achieved at least a 25% reduction in body weight, compared to 16.1% for Wegovy, according to Eli Lilly (NYSE:LLY).
"We are thrilled that today's findings showed the superior weight loss of Zepbound, which helped patients achieve 47% more relative weight loss compared to Wegovy," said Leonard Glass, Eli Lilly's senior vice president of global medical affairs.
He emphasized that Zepbound's dual GIP and GLP-1 receptor agonist mechanism makes it a unique obesity treatment, offering transformative benefits to patients.
The trial also reaffirmed Zepbound's safety profile, which aligned with previous SURMOUNT studies. The most common side effects for both medications were gastrointestinal issues, typically mild to moderate in severity.
Lilly plans to publish the results in a peer-reviewed journal and present them at a medical meeting next year. Zepbound is already FDA-approved for obesity and overweight management in the U.S.
This announcement bolsters Eli Lilly's position in the growing obesity treatment market, where demand for effective weight-loss therapies continues to rise.
Reacting to the news, analysts at Morgan Stanley (NYSE:MS) said they "view the update as an incremental positive for LLY shares. The bank, which reiterated its Overweight rating on the stock, added: "The results are another data point supporting the low-20s% weight loss profile of Zepbound (setting the bar for competing therapies), and may have marketing benefits for LLY, though we note the level of supply constraints from both players remains a near-term question."